Seal for filter bed cleaners



y 16, 1940- w. c. LAUGHLIN 7,988

' SEAL FOR FILTER BED CLEANERS Filed Nov. 2, 1938 3 Sheets-Sheet 1 wzz/4/W zgwawz/w, .g

ATTORNEY.

y 16, 1940- A w, c. LAUGHLIN 07,988

SEAL FOR FILTER BED CLEANERS Filed Nov. 2, 1938 3 Sheets-Sheet 2 INVENTOR. W/ZZ/HM 0. 4406774 //V ATTORNEY.

y 16, 1940- w. c. LAUGHLIN 2,207,988

SEAL FOR FiLTER BED CLEANERS Filed Nov. 2, 1938 3 Sheets-Sheet 3 IN VENT OR.

W/dl/fll}? 0. 40052 //v,. i LQLM ATTORNEY.

Patented July 16,1940 i I. 2,207,988

UNITED STATES PATENT OFFICE SEAL FOR FILTER BED CLEANERS William G. Laughlin, New York, N. Y., assignor to Filtration Equipment Corporation, Bound Brook, N. J a corporation of Delaware Application November 2, 1938, Serial No. 238,371

9 Claims. (01. 210-128).

This invention relates to cleaning devices for anism for agitating the sand or other loose submerged filters of loose material of the type material of the filter bed and for removused in clarifying water or sewage, and more ing the accumulated dirt and impurities particularly to traveling cleaning devices of this therefrom, preferably by a washing operation,

type which travel over the surface of the filter and for discharging the impurities from the 5 bed either continuously or intermittently and cleaner in the form of an aqueous suspension constitutes an improvement upon the mechanism known as wash water. There are a number of shown and described in the co-pending applicaknown cleaning devices of this nature which are tion of Charles E. Fraser, Serial No. 152,771. now used for sand filters of the submerged type,

10 Objects of the invention are to increase the some of which operate merely by mechanical effectiveness of the cleaner and particularly to agitation of the sand, others by the injection prevent contamination of filtered efiiuent by adof jets of water into the sand and still others mixture with dirt removed from the filter during by the agitation of magnetite sand or other r the cleaning, operation. A more specific object magnetic material by means of an intermittently toward the accomplishment of these purposes is operating electromagnet. However, all the to provide a traveling cleaning device having a cleaning devices of which I am aware operate seal which will effectively prevent the influx or upon the principle of agitating successive porescape of water or sewage from under'the lower tions of the filter bed and withdrawing the accuedges of the cleaner during the cleaning operamulated impurities therefrom in the form of a tion. Water suspension, and it is an object of my 2 In rapid filtration processes and particularly invention to improve the effectiveness of any in the clarification of sewage and industrial cleaner of this type by preventing admixture of wastes by rapid filtration, it is necessary to use the wash Water used therein with the filtered a relatively thin bed of filtering material such efiluent.

as sand and relatively high rates of flow. In To this end, the invention contemplates a 25. such an installation, the thin bed of filtering traveling cleaner for sand filters which includes material, therefore, must hold back and retain a movable cleaner tank adapted to travel over relatively large amounts of solid material per the filter bed, to wash a portion ofthe bed and unit of time, and Without a more or less conremove the impurities thus separated, With detinuous cleaning, it soon becomes clogged and formable rollers at each end of the cleaner tank 0, offers a greatly increased resistance to the flow making sealing contact with the walls of the of water therethrough. This resistance, in turn, tank and with the filter bed. In contradistinccuts down the rated capacity of the filter or else tion to the rigid rollers of the above-mentioned increases back pressure to a point where a much Fraser application, the present invention congreater operating head is necessary. templates the use of deformable rollers of rubber 35 By reason of the necessity of more or less or the like so that not only do they make a water continuous cleaning, modern submerged filters lubricated wiping contact with the cleaner tank both of the upflow and downflow type are so walls due to the fact that they are submerged designed and constructed that the clarified eflluin the qu b t at e Same time, due to the cut from the filter passes out of the filter chame p sitio O e equipment With e n 0- the 40 her at a level above that of the filter bed, thus bed, the rollers will be deformed at the beds ensuring that the filter will be covered by .one surface so as to make a substantially flattened or two feet of liquid at all times. The fiow of plane surface contact therewith as the rollers roll impure water or sewage to be clarified reaches over the bed with the cleaner tank.

the influent side of the filter bed under a hydro- The invention further contemplates the de- 45 static head or pressure which represents a suffitailed arrangement, combination and construccient water head above that of the outflow to tion of parts more fully hereinafter described overcome the fiow resistance due to the filter, and and shown in the accompanying drawings. thus causes the liquid to flow through the filter In the drawings bed by reason of its hydrostatic pressure. .A Fig. l is an elevation of a device embodying 5,0 traveling cleaning device is mounted over the the invention, having one pair of end Walls of filter bed on an arm or trackway and moves the cleaner tank removed; continuously or intermittently along the length Fig. 2 is a side view along the line 2-2 of Fig.1; of the filter bed. Fig. 3 is a detailed View of one end of a rubber The cleaner is provided with a cleaning mechsealing roller; 55,

Fig. 4 is a bottom perspective view showing the details of construction of the cleaner tank.

Referring now with particularity to a preferred embodiment of the invention illustrated, the cleaner tank consists of side walls I and 2 enclosing therebetween a divergent pair of end walls 3 and a similar pair 4 at the other end thereof. A top wall 5 connected with the side walls I and 2 serves to support the driving motor 6 and associated mechanism which latter includes a shaft 1 to the ends of which traction wheels 8 are secured and which move upon tracks 9 mounted above the side walls ll! of the sewage tank. As shown, the stub shaft H from the prime mover 6 is provided with a mutilated gear l2 meshing with a larger gear [3. Consequently, rotation of the prime mover in either direction will, through the instrumentalities of gears l2 and I3, drive the entire cleaner mechanism intermittently over the filter bed in either direction.

The filter bed may consist of a grid l4 carrying a coarse mesh I5 adapted to receive and hold thereon a desired depth of sand I6 of any desired variety, either magnetic or not, as the case may be.

It will be observed that in view of the fact that the side walls 1 and 2 of the cleaner tank extend a substantial distance into the filter bed It as at I1, leakage of dirty water from above the filter bed into the cleaner chamber is thus prevented at that point.

Within each pair of divergent end walls 3 and 4 of the cleaner tank are sealing rollers IB and I9. These rollers are of deformable material, preferably rubber or the like, so arranged as to make wiping contact with the inside of the divergent walls within which they are located and also wiping sealing contact with the end walls of the cleaner tank. These rollers are mounted upon a shaft 2E! carried in bearings 2| and provided with sprockets 22 which, through chains 23 and sprockets 24 mounted on drive shafts I, serve to rotate the rollers.

The rollers themselves are of a size sufficient to not only make the necessary wiping contact with the pairs of divergent walls 3 and 4 but also to make rolling contact with the filter bed I6. Due to the fact that the invention contemplates rollers of deformable nature such as soft rubber or the like, they will be flattened into a substantially plane contact with the filter bed as they move thereover and thus prevent leakage of dirty water from outside the cleaner tank thereinto.

It is to be understood that in the preferred form of the invention, the cleaner mechanism is principally supported on its trackway 9 and only a sufficient weight bears on the soft rollers l8 and I9 to cause them to slightly flatten. However, these rollers are not relied upon for traction.

Within the main body of the cleaner tank is a plate 25 from which is suspended an electromagnet 26 on an adjustable support 21 so that the position of the magnet may be adjusted with relation to the surface of the bed l 6. The operation of this magnet is substantially similar to the operation of the electromagnet referred to in the Laughlin Patent 1,872,759 and, hence, will not be described in detail here. Suffice it to say that this magnet is adapted to be intermittently energized so that where the filter bed is of magnetite sand, a portion of such dirty sand will be withdrawn from the bed in an upward direction and the adhering dirt cleaned or sprayed therefrom. When the magnet is de-energized, the

cleaned sand will, under the action of gravity,

including the dirt removed from the sand particles, is then sucked into the top of pipe 28 and under the action of pump 29 driven by motor 30, discharged through the wash water exit 3| for disposal.

It will be noted from the above that the aforementioned construction provides a cleaner tank within which the entrained dirt and impurities may be separated from the filter bed material and removed therefrom. This part of the construction is well known and is illustrated merely as one type of cleaning mechanism which may be employed.

The important feature of the invention is the fact that this cleaner tank is at all times sealed against the entrance of unfiltered sewage or other liquid being purified so that at no time may such dirty water reach the clean efiiuent below the filter bed except by passage through the bed which, of course, has the effect of cleaning the liquid of its impurities. The sealing rollers at each end of the cleaner tank effectively prevent the passage of this dirty water past the ends of the tank. The tank is entirely driven by the prime mover 6 mounted on the carriage above the tank, although the parts are so arranged that sufficient weight is placed upon the rollers to cause them to be deformed as they make contact with the filter bed. This deformation results in a substantial area of flat contact between the roller and the filter bed and, consequently, prevents leakage of liquid at this point. Due to the While the invention has been shown and de-' scribed with particular reference to specific embodiments, it is to be understood thatit is not to be limited thereto but is to be construed broadly and restricted only by the scope of the claims.

I claim:

l. A traveling cleaner for sand filters comprising in combination a filter bed, a movable cleaner tank adapted to travel over the filter bed and provided with means for removing impurities washed from the bed, and rotative sealing means extending across the ends of the tank and making sealing contact with the side and end walls of the tank to prevent passage of fluid therebetween, the periphery of said rotating sealing means comprising a material' capable of temporary deformation, a part of the said periphery making a sealing contact with the filter bed.

2. The combination of claim 1 in which the deformable portion of the sealing means in contact with the filter bed is rubber.

3. The combination of claim 1 in which the periphery of the sealing means is rubber, making substantially plane surface contact with the filter bed.

sealing means includes a rubber roller.

5. The combination of claim 1 in which the sealing means makes wiping contact with a wall of the, cleaner tank.

6. A traveling cleaner for sand filters compris-v ing in combination a filter bed, a movable cleaner tank adapted to travel over the filter bed and provided with means for removing impurities Washed from the bed, said cleaner tank having ing in combination a filter bed, a movable cleaner tank adapted to travel over the filter bed and provided with means for removing impurities I washed. from the bed, said cleaner tank having two diverging walls at each end thereof separated toward the filter bed, side walls contacting with the divergent walls, sealing means to prevent passage of fluid between Said side walls and the filter bed, and a deformable rubber sealing roller in the space between each pair of divergent walls making wiping contact therewith and with the side walls and a deformed fiat rolling sealing contact with the filter bed.

8. The combination of claim 7 with means to move the cleaner tank and rollers over the filter bed.

9. The combination of claim 1 in which the periphery of the rotating sealing means is of resilient material.

- WILLIAM C'. LAUGHLIN. 

